Overall, I’m in favor of A Camping Trip.
Camp atmosphere, summer, tents. There’s plenty of room to come up with story hooks for different characters: the camp counselor, the troublemaker girls, the nurse, a shady hermit who lives far away from the camp, as well as a mythical lady by the lake and other clichés—but clichés in a good sense, not a bad one.
As for gameplay, you could introduce some kind of camp-style competitions (swimming, chopping wood, starting campfires, searching for a missing child, etc.). Or you could take a different approach and make card battles the core of the gameplay. Cards could be found around locations, bought in a shop, and rare ones earned by defeating characters (you could also reward a sex scene for winning against them, and for losing, some other scene tied to their fetish).
Also, since summer is coming up, I think a game like this would match the real-life atmosphere perfectly and could make immersion even stronger.
Thanks for all your games, and good luck with developing the next ones!